Litter mat



FIG. 1 is a top plan view of a litter mat showing our new design;

FIG. 2 is a left side view thereof, the right side view being identical;

FIG. 3 is a front edge view thereof, the rear edge view being identical;

FIG. 4 is an enlarged partial view of the area labeled “4” in FIG. 1;and,

FIG. 5 is a cross-section taken along line 5-5 in FIG. 4.

CLAIM The ornamental design for a litter mat, as shown and described.